Ventilating fan assembly



July 17, 1962 L. L. ALLDRITT ETAL 3,044,689

VENTILATING FAN ASSEMBLY Filed May 8, 1958 INVENTORS LAWRENCE L.ALLDRITT DELLA MAY ALLDRITT A TTORA I EV United States 3,044,689Patented July 17, 1962 lice ' Filed May s, 1958, Ser.'No. 733,886

3 Claims. 01. 230-273 The present invention relates to ventilating andcooling fan assemblies, and more particularly to 'belt driven fanassemblies intended and adapted for attic and wall mounting, inresidences and oflice buildings and factories and other buildings, bothof frame and masonry con- 7 struction.

An object of the invention is to provide a fan assembly structure forceiling or attic or wall installation, which has a supporting andmounting structure of compact form and arrangement, thus requiring aminimum of space and depth of wall or frame for installation, so thatthe fan assembly can be substantially completely encompassed within thethickness of an average wall of a frame or masonry house, and so thatin'attic installations a minimum of space will be required and the fancan be mounted to hang down inside the joists instead of resting uponand projecting above the joists.

A further object of the present invention is the provision of aventilating fan and mounting therefor such that the parts aresubstantially balanced to distribute any strain from the fan and motormounting and the drive belt therebetween. 7

Still another object of the present invention is the provision of aventilating fan assembly having means resiliently mounting the rotatablefan member so as to avoid pounding or hammering of the fan unit.

Another object of the present invention is the provision of a fan andmounting structure which is simple to install and of which all parts canbe easily reached for servicing and the like.

Finally, it is an object of the present invention to provide aventilating fan assembly which will be easy and inexpensive tomanufacture, simple to operate, maintain and repair, and rugged anddurable in use.

Other objects and advantages of the present invention will becomeapparent from a consideration of the following description, taken inconnection with the accompanying drawing, in which:

FIGURE 1 is a view in perspective showing the ventilating-fan of thepresent invention from the intake side;

FIGURE 2 is a view in edge elevation showing the fan and mountingstructure; and

FIGURE 3 is an elevational view looking at the intake side of themounting structure with the drive motor and rotatable fan unit removed.

Referring now to the drawing in greater detail, there is shown aventilating fan assembly comprising a substantially rectangular flatplate having an upstanding flange 12 disposed on one side of the planethereof entirely about the edges of the plate. Plate 10 is provided witha circular central opening 14 bounded by a venturi ring 16 integral withplate 10 and extending away from the plane of plate 10 on the sidethereof opposite flange 12. Obviously, plate 10 with its flange andventuri ring may be constructed by forming opening 14, spinning outventuri ring 16, and bending up and welding flange 12.

Secured flat against the same side of plate 10 as flange 12 is auniplanar integral Z-shaped torsion bar 18, which may be a steel rod ofround bar stock bent at two places so as to have a straight mid-portion20 and a pair of oppositely angularly related legs 22 and 24 which arestraight and in the illustrated embodiment are parallel to each other.Each leg 22 and '24 is secured adjacent its ends to plate 10 by means ofwelds 26' so that leg 22 is disposed adjacent corner 30 of plate 10 andflange 12 while leg 24 is disposed adjacent diagonally opposite corner32 of plate 10 and flange '12. The ends of leg 22 lie on opposite sidesof an imaginary line 28 joining diagonally opposite corners 30 and 32,as do also the ends of leg 24 and the welds 26 adjacent those leg ends.If the points of securement of legs 22 and 24 to plate 10 on one side'ofline 28 are joined by an imaginary line 34 and the points of securementoflegs 22 and 24 on the other side of line 28 are joined by an imaginaryline 36, it will be noted that line 28 lies substantially.

mid-way between and substantially parallel to lines 34 and 36.

Secured in holes 38 through plate 10 is the mounting bracket for anelectric drive motor 40 which is thus mounted on plate 10 on the sameside of the plane of the plate as venturi ring 16. Motor 40 has a driveshaft 42 which extends through hole 44 in plate 10 and terminates on theflange side of plate 10 in a relatively small drive pulley 46.

Mounted for rotation coaxially ofopening 14 on midportion 20 is a fan 48having a coaxial fan shaft 50 rotatable in a bracket 52 fixedly securedon mid-portion 20. On the free end of fan shaft 50 opposite fan 48 frombracket 52 is a relatively large fan pulley 54 drivingly interconnectedwith drive pulley 46 by a conventional drive belt 56. It should beparticularly noted that drive belt 56 extends in the same generaldirection as line 28 and that drive shaft 42 is disposed at all timesbetween lines 34 and 36, either on or a very small distance on eitherside of line 28. It should also be noted that fan shaft 50 isperpendicular to but spaced from mid-portion 20, which is to say thattheaxis of rotation of fan 48 and the torsional axis of mid-portion 20are spaced apart a substantial distance. Also, fan 48 beingsubstantially heavier than fan pulley 54, the centroid of the rotatablefan unit is spaced a still greater distance from the torsional axis ofmid-portion 20. It will further be observed that the angle betweenmid-portion 20 and the line 28 is very small and substantially less than45", so that longitudinal stresses imparted through drive belt 56 willbe borne by mid-portion 20 largely in axial tension or compression.

Considering the fan and its mounting as a resilient structure of limitedflexibility, it will also be seen that the axial stresses in mid-portion.20 will to some extent be relieved by angularly related legs 22 and 24somewhat in the manner of a clip spring and these stresses and forceswill be equally distributed throughout the fan and its frame by thelocation of the secured ends of legs 22 and 24 on opposite sides of line28. Moreover, the securement of legs 22 and 24 as above described alsoassures that the weight of fan 48 and the other factors tending tomisalign fan shaft 50 from its coaxial relationship in opening 14 willbe largely borne in torsion by mid-portion 20 in a very firm butsomewhat resilient manner thanks to the oppositely angular dispositionof legs 22 and 24 relative to mid-portion 20, so that these forces andstresses will be evenly distributed about plate 10 and flange 12.Finally, it will be noted that the provision of flange 12 aboutrectangular plate 10 creates a structure which would inevitably have atendency to rack or twist about line 28 were it not for the mounting oftorsion bar 18 as above described.

In view of the foregoing disclosure and discussion, it will be obviousthat all of the initially recited objects of the present invention havebeen achieved.

Although the present invention has been described and illustrated inconnection with a preferred embodiment, it is to be understood thatmodifications and variations may be resorted to without departing fromthe spirit of this invention, as those skilled in this art will readilyunderstand. Such modifications and variations are considered to bewithin the purview and scope of the present invention as defined by theappended claims.

What is claimed is:

1. A ventilating fan assembly for installation in buildings, comprisinga substantially rectangular flat plate having a circular central openingwith a venturi ring extending outwardly on one side of the plane of theplate and a marginal flange extending outwardly on the other side of theplane of the plate, an integral uniplanar Z-shaped torsion bar having astraight mid-portion terminating at its ends in a pair of legsoppositely angularly related to the midportion, each leg being securedadjacent each of its ends to the flange side of the plate on oppositesides of a line joining diagonally opposite corners of the plate, themidportion extending across the opening, a fan mounted on themid-portion for rotation coaxially of the opening, an electric motormounted on the same side of the plate as the venturi ring and having adrive shaft extending through a hole in the plate, and means disposed onthe flange side of the plate and drivingly connecting the fan with thedrive shaft.

2. A ventilating fan assembly as claimed in claim 1, the drive shaftbeing disposed between lines interconnecting the ends of the legsdisposed on each side of said line joining diagonally opposite cornersof the plate.

3. A ventilating fan assembly for installation in buildings, comprisinga substantially rectangular plate having an outer marginal flange and acircular opening through the plate, an integral uniplanar Z-shapedtorsion bar having a straight mid-portion terminating at its ends in apair of legs oppositely angularly related to the mid-portion, each legterminating at one end in an end of the midportion and being spaced atthe other end a substantial distance from the mid-portion, each legbeing secured adjacent each of its ends to the plate on opposite sidesof a line joining diagonally opposite corners of the plate, themid-portion having a length greater than the diameter of the opening andextending across the opening, a fan mounted on the mid-portion forrotation coaXially of the opening, an electric motor mounted on theplate and having a drive shaft, and means drivingly connecting the fanwith the drive shaft.

References Cited in the file of this patent UNITED STATES PATENTS2,746,674 Alldritt et a1 May 22, 1956 2,708,373 Werner May 17, 19552,874,898 Bayhi Feb. 24, 1959

